JP3606517B2 - Hybrid circuit - Google Patents

Description

ここで、Ｃ＝１／√２、θ＝９０°とすると、前記（１）式は、下記（２）式のように表される。
【数２】
Ｓ_１２＝Ｓ_２１＝Ｓ_３４＝Ｓ_４３＝１／√２ ・・・・・・・・・ （２）
また、端子Ｔ_１−端子Ｔ_３の電圧結合係数Ｓ_１３、端子Ｔ_３−端子Ｔ_１の電圧結合係数Ｓ_３１、端子Ｔ_２−端子Ｔ_４の電圧結合係数Ｓ_２４、端子Ｔ_４−端子Ｔ_２の電圧結合係数Ｓ_４２は、下記（３）式で表される。
【数３】

ここで、Ｃ＝１／√２、θ＝９０°とすると、前記（１）式は、下記（４）式のように表される。
【数４】
Ｓ_１３＝Ｓ_３１＝Ｓ_２４＝Ｓ_４２＝−ｊ／√２ ・・・・・・・・ （４）
【００１２】
図６ないし図８は、本実施の形態のハイブリッド回路の一例の電気的特性を示すグラフである。
この図６ないし図８に示すグラフは、本実施の形態のハイブリッド回路を実際に試作して、その電気的特性を測定した結果を示すグラフである。
試作したハイブリッド回路の寸法は、以下の通りである。
（１）シールドケース１の内部の形状
一辺の長さ（図３に示すＬｃ）が１００ｍｍで、高さ（図２に示すＬｄ）が１００ｍｍの立方体。
（２）結合線路（１１，１２）の形状
傾斜部２の長さが１５０ｍｍ（したがって、λｏは６００ｍｍ、ｆｏは０．５ＧＨｚ）、幅（図４のＷ）が７０ｍｍ、厚さが２ｍｍ。
（３）内部導体１３の形状
内径が３１．３ｍｍ、外径が３３．４ｍｍ。
（４）外部導体１４の形状
内径が７６．９ｍｍ、外径が７９．４ｍｍ。
【００１３】
図６は、実際に試作した本実施の形態のハイブリッド回路の端子Ｔ_１−端子Ｔ_２間の出力電圧の位相と、端子Ｔ_１−端子Ｔ_３間の出力電圧の位相特性を示すグラフである。
図６において、横軸は周波数（ＭＨｚ）でメモリ間隔は５０ＭＨｚ、中心周波数は０．６ＧＨｚ、縦軸は位相量でメモリ間隔は４５°である。
また、Ａが端子Ｔ_１−端子Ｔ_２間の出力電圧の位相を、Ｂが端子Ｔ_１−端子Ｔ_３間の出力電圧の位相を表し、図６から分かるように、端子Ｔ_１に電圧を印加したときに、端子Ｔ_２から出力される出力電圧と、端子Ｔ_３から出力される出力電圧との間の位相差は９０°になっている。
なお、図６の端子Ｔ_１−端子Ｔ_２間の出力電圧の位相のグラフにおいて、周波数が０．４７ＧＨｚ（図６のＡのグラフの２の点）のときの位相は−１３０．４°、周波数が０．５０３ＧＨｚ（図６のＡのグラフの１の点）のときの位相は−１４４．９２°、周波数が０．６９２ＧＨｚ（図６のＡのグラフの３の点）のときの位相は１３１．２５°、周波数０．７７０ＧＨｚ（図６のＡのグラフの４の点）のときの位相は９５．７７５°である。
また、図６の端子Ｔ_１−端子Ｔ_３間の出力電圧の位相のグラフにおいて、周波数が０．４７ＧＨｚ（図６のＢのグラフの２の点）のときの位相は１３９．５１°、周波数が０．５０３ＧＨｚ（図６のＢのグラフの１の点）のときの位相は１２４．８４°、周波数が０．６９２ＧＨｚ（図６のＢのグラフの３の点）のときの位相は４０．８４３°、周波数０．７７０ＧＨｚ（図６のＢのグラフの４の点）のときの位相は４．０７４６°である。
【００１４】
図７は、実際に試作した本実施の形態のハイブリッド回路の端子Ｔ_１−端子Ｔ_２間の出力電圧と、端子Ｔ_１−端子Ｔ_３間の出力電圧の減衰特性を示すグラフである。
図７において、横軸は周波数（ＭＨｚ）でメモリ間隔は５０ＭＨｚ、中心周波数は０．６ＧＨｚ、縦軸は減衰量でメモリ間隔は１ｄＢである。
また、Ａが端子Ｔ_１−端子Ｔ_２間の出力電圧の減衰量、Ｂが端子Ｔ_１−端子Ｔ_３間の出力電圧の減衰量を表し、図７から分かるように、０．４７ＧＨｚ〜０．７０ＧＨｚの間で、端子Ｔ_１に電圧を印加したときに、端子Ｔ_２から出力される出力電圧の減衰量、および、端子Ｔ_３から出力される出力電圧の減衰量は、ほぼ３ｄＢとなっている。
なお、図７の端子Ｔ_１−端子Ｔ_２間の出力電圧の減衰量のグラフにおいて、周波数が０．４７ＧＨｚ（図７のＡのグラフの２の点）のときの減衰量は−３．５０８８ｄＢ、周波数が０．５０３ＧＨｚ（図７のＡのグラフの１の点）のときの減衰量は−３．２９３５ｄＢ、周波数が０．６９２ＧＨｚ（図７のＡのグラフの３の点）のときの減衰量は−３．０５２４ｄＢ、周波数０．７７０ＧＨｚ（図７のＡのグラフの４の点）のときの減衰量−３．５００５ｄＢである。
また、図７の端子Ｔ_１−端子Ｔ_３間の出力電圧の減衰量のグラフにおいて、周波数が０．４７ＧＨｚ（図７のＢのグラフの２の点）のときの減衰量は−２．５９６９ｄＢ、周波数が０．５０３ＧＨｚ（図７のＢのグラフの１の点）のときの減衰量は−２．７７４４ｄＢ、周波数が０．６９２ＧＨｚ（図７のＢのグラフの３の点）のときの減衰量は−３．０８９ｄＢ、周波数０．７７０ＧＨｚ（図７のＢのグラフの４の点）のときの減衰量−２．９１２５ｄＢである。
【００１５】
図８は、実際に試作した本実施の形態のハイブリッド回路の端子Ｔ_１−端子Ｔ_４間の出力電圧と、端子Ｔ_２−端子Ｔ_３間の出力電圧の減衰特性を示すグラフである。
図８において、横軸は周波数（ＭＨｚ）でメモリ間隔は５０ＭＨｚ、中心周波数は０．６ＧＨｚ、縦軸は減衰量でメモリ間隔は１０ｄＢである。
また、Ａが端子Ｔ_１−端子Ｔ_４間の出力電圧の減衰量、Ｂが端子Ｔ_２−端子Ｔ_３端子Ｔ_１−端子Ｔ_３間の出力電圧の減衰量を表し、図８から分かるように、０．４７ＧＨｚ〜０．７０ＧＨｚの間で、端子Ｔ_１に電圧を印加したときに、端子Ｔ_２から出力される出力電圧の減衰量、および、端子Ｔ_２に電圧を印加したときに、端子Ｔ_３から出力される出力電圧の減衰量は、ほぼ３０ｄＢとなっており、端子Ｔ_１に電圧を印加したときに、端子Ｔ_２から出力される出力電圧、および、端子Ｔ_２に電圧を印加したときに、端子Ｔ_３から出力される出力電圧は、充分減衰されていることが分かる。
なお、図８の端子Ｔ_１−端子Ｔ_４間の出力電圧の減衰量のグラフにおいて、周波数が０．４７ＧＨｚ（図８のＡのグラフの２の点）のときの減衰量は−２５．３０４ｄＢ、周波数が０．５０３ＧＨｚ（図８のＡのグラフの１の点）のときの減衰量は−２．７７４４ｄＢ、周波数が０．６９２ＧＨｚ（図８のＡのグラフの３の点）のときの減衰量は−２０．４３９ｄＢ、周波数０．７７０ＧＨｚ（図８のＡのグラフの４の点）のときの減衰量−１６．７２３５ｄＢである。
また、図８の端子Ｔ_２−端子Ｔ_３間の出力電圧の減衰量のグラフにおいて、周波数が０．４７ＧＨｚ（図８のＢのグラフの２の点）のときの減衰量は−２５．２７６ｄＢ、周波数が０．５０３ＧＨｚ（図８のＢのグラフの１の点）のときの減衰量は−２７．９８６ｄＢ、周波数が０．６９２ＧＨｚ（図８のＢのグラフの３の点）のときの減衰量は−２１．０４４ｄＢ、周波数０．７７０ＧＨｚ（図８のＢのグラフの４の点）のときの減衰量−１６．８７８ｄＢである。
【００１６】
図９は、本実施の形態のハイブリッド回路を使用した空中線共用器の概略構成を示すブロック図である。
図９に示す空中線共用装置では、第２のハイブリッド回路２２の第４の端子（Ｔ_２４）と、第４のハイブリッド回路２４の第１の端子（Ｔ_４１）とが互いに接続され、また、第２のハイブリッド回路２２の第１の端子（Ｔ_２１）は、無反射終端器（Ｒ）に接続され、第４のハイブリッド回路２４の第４の端子（Ｔ_４４）は、アンテナ（ＡＮＴ）に接続される。
また、第１のハイブリッド回路２１の第１の端子（Ｔ_１１）は、第１のチャネル（ｃｈ１）の送信波を出力する送信機に接続され、また、第３のハイブリッド回路２３の第１の端子（Ｔ_３１）は、第２のチャネル（ｃｈ２）の送信波を出力する送信機に接続される。
さらに、第１のハイブリッド回路２１の第４の端子（Ｔ_１４）、および第３のハイブリッド回路２３の第４の端子（Ｔ_３４）は、無反射終端器（Ｒ）に接続される。
【００１７】
また、第１のハイブリッド回路２１の第２の端子（Ｔ_１２）と、第２のハイブリッド回路２２の第２の端子（Ｔ_２２）との間、並びに、第１のハイブリッド回路２１の第３の端子（Ｔ_１３）と、第２のハイブリッド回路２２の第３の端子（Ｔ_２３）との間には、第１の帯域通過フィルタ（３０，３１）が接続される。
同様に、第３のハイブリッド回路２３の第２の端子（Ｔ_３２）と、第４のハイブリッド回路２４の第２の端子（Ｔ_４２）との間、並びに、第３のハイブリッド回路２３の第３の端子（Ｔ_３３）と、第４のハイブリッド回路２４の第３の端子（Ｔ_４３）との間には、第２の帯域通過フィルタ（３２，３３）が接続される。ここで、第１のハイブリッド回路２１、第２のハイブリッド回路２２、および帯域通過フィルタ（３０，３１）は、第１のチャネル（ｃｈ１）の送信波を通過させる定インピーダンス帯域通過フィルタを、並びに、第３のハイブリッド回路２３、第４のハイブリッド回路２４、および帯域通過フィルタ（３２，３３）は、第２のチャネル（ｃｈ２）の送信波を通過させる定インピーダンス帯域通過フィルタを構成する。
ここで、ハイブリッド回路（２１〜２４）は、本実施の形態のハイブリッド回路が使用される。
【００１８】
以下、図９に示す空中線共用装置の動作を簡単に説明する。
第１のハイブリッド回路２１の第１の端子（Ｔ_１１）から入力された第１のチャネル（ｃｈ１）の送信波は、それぞれ帯域通過フィルタ（３０，３１）を通って、第２のハイブリッド回路２２に入力され、第２のハイブリッド回路２２の第４の端子（Ｔ_２４）から出力される。
この第２のハイブリッド回路２２から出力された第１のチャネル（ｃｈ１）の送信波は、第４のハイブリッド回路２４に入力され、帯域通過フィルタ（３２，３３）で全反射され、第４のハイブリッド回路２４の第４の端子（Ｔ_４４）から出力され、アンテナ（ＡＮＴ）から放射される。
また、第３のハイブリッド回路２３の第１の端子（Ｔ_３１）から入力された第２のチャネル（ｃｈ２）の送信波は、それぞれ帯域通過フィルタ（３２，３３）を通って、第４のハイブリッド回路２４に入力され、第４のハイブリッド回路２４の第４の端子（Ｔ_４４）から出力され、アンテナ（ＡＮＴ）から放射される。以上、本発明者によってなされた発明を、前記実施の形態に基づき具体的に説明したが、本発明は、前記実施の形態に限定されるものではなく、その要旨を逸脱しない範囲において種々変更可能であることは勿論である。
【００１９】
【発明の効果】
本願において開示される発明のうち代表的なものによって得られる効果を簡単に説明すれば、下記の通りである。
本発明によれば、λ／４結合形３ｄＢハイブリッド回路において、電気的特性を損なうことなく、電力容量を向上させることが可能となる。
【図面の簡単な説明】
【図１】本発明の実施の形態のλ／４結合形３ｄＢハイブリッド回路の上平面を示す平面図である。
【図２】図１に示すλ／４結合形３ｄＢハイブリッド回路の一側面を示す側面図である。
【図３】図２に示すＡ−Ａ’切断線で切断した断面を示す断面図である。
【図４】本発明の実施の形態の結合線路を説明するための図である。
【図５】本発明の実施の形態の結合線路の幅を説明するための図である。
【図６】本発明の実施の形態のλ／４結合形３ｄＢハイブリッド回路の端子Ｔ_１−端子Ｔ_２間の出力電圧と、端子Ｔ_１−端子Ｔ_３の間の出力電圧との間位相特性を示すグラフである。
【図７】本発明の実施の形態のλ／４結合形３ｄＢハイブリッド回路の端子Ｔ_１−端子Ｔ_２間の出力電圧と、端子Ｔ_１−端子Ｔ_３の間の出力電圧の減衰特性を示すグラフである。
【図８】本発明の実施の形態のλ／４結合形３ｄＢハイブリッド回路の端子Ｔ_１−端子Ｔ_４間の出力電圧と、端子Ｔ_２−端子Ｔ_３の間の出力電圧の減衰特性を示すグラフである。
【図９】本発明の実施の形態のλ／４結合形３ｄＢハイブリッド回路を使用する空中線共用器の概略構成を示すブロック図である。
【図１０】従来のハイブリッド回路の構造を示す模式斜視図である。
【図１１】従来のハイブリッド回路の構造を示す要部断面図である。
【図１２】従来のハイブリッド回路の側面を示す側面図である。
【符号の説明】
１…シールドケース、２…傾斜部、３、４…端子接続部、１１，１２…結合線路、１３…内部導体、１４…外部導体、１５…スペーサ、２１〜２４…ハイブリッド回路、３０〜３３…帯域通過フィルタ、ＡＮＴ…アンテナ、Ｒ…無反射終端器。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hybrid circuit, and more particularly to a 3 dB hybrid circuit with improved power capacity.
[0002]
[Prior art]
In mobile communication devices, broadcasting devices, etc., hybrid circuits are used for branching high frequency signals or synthesizing high frequency signals.
FIG. 10 is a schematic perspective view showing the structure of a conventional λ / 4 coupled 3 dB hybrid circuit (hereinafter simply referred to as a hybrid circuit).
As shown in FIG. 10, in the conventional hybrid circuit, two coupled lines (or strip lines) (11, 12) are arranged in a shield case (housing) 1.
The line length (L) of the coupled lines (11, 12) is approximately λo / 4 (L≈λo / 4) when the wavelength of the design center frequency of the hybrid circuit is λo.
Further, the four terminals (T _{1 to} T ₄ ) are constituted by coaxial feed pipes each constituted by an inner conductor (13 _{1 to} 13 ₄ ) and an outer conductor (14 _{1 to} 14 ₄ ). has one end the first internal conductor 13 _first terminal _{T 1,} the other end is connected to the inner conductor 13 of the _third terminal _{T 3,} the coupling line 12 has one end a second inner conductor terminal _{T 2} 13 ₂ and the other end connected to the fourth terminal _{T 4} inner conductor 13 _4.
Further, in FIG. 10, the shield case 1 is represented by a solid line for easy understanding of the internal structure.
FIG. 11 is a cross-sectional view of the main part showing the actual structure of the hybrid circuit shown in FIG. 10, and is a cross-sectional view showing the cross-sectional structure along the line BB ′ shown in FIG.
12 is a side view showing one side surface of the hybrid circuit shown in FIG. 11, and shows the side surface seen from the direction C shown in FIG.
In FIG. 11, reference numerals 15 ₁ to 15 ₄ denote spacers that support the internal conductors (13 _{1 to} 13 ₄ ).
[0003]
[Problems to be solved by the invention]
The conventional hybrid circuit shown in FIGS. 11 and 12 has a smaller shield case 1 or a smaller outer diameter of the inner conductor of the terminal than the wavelength (λo) of the design center frequency of the hybrid circuit. In this case, good electrical characteristics can be obtained, but the electrical characteristics deteriorate when the size of the shield case 1 is large or the outer diameter of the inner conductor of the terminal is larger than the wavelength (λo). Has the disadvantage of
Hereinafter, this point will be described.
In the hybrid circuit shown in FIG. 11 and FIG. 12, when the length of the shield case 1 in the short direction is A and the thickness of the shield case 1 is B, generally, B / A≈0.5. , A is 100 mm (A = 100), B is 50 mm (B = 50).
As a result of the experiment, the width of the coupled lines (11, 12) (W1 in FIG. 12) in this case was 35 mm.
Assuming that the thickness of the coupled lines (11, 12) is 5 mm, the perimeter when cut along a plane orthogonal to the extending direction of the coupled lines (11, 12) is 80 mm (= 35 × 2 + 5 × 2). Become.
[0004]
Further, when the outer diameter of the inner conductor 13 of the coaxial feeding pipe constituting the input terminal or the output terminal is 33.4 mm in terms of power capacity, the circumferential length of the inner conductor 13 of the coaxial feeding pipe is 105 (≈ π × 33.4).
Therefore, in the case described above, the peripheral length of the coupling lines (11, 12) is approximately 76% (≈100 × 80/105) lower than the circumferential length of the inner conductor 13 of the coaxial feeder tube. become.
Since high frequency waves such as microwaves are conducted on the surface of the conductor, the power capacity of the hybrid circuit 10 shown in FIGS. 11 and 12 is about 76% lower than the power capacity of the coaxial feeder. Become.
In order to increase the width of the coupled lines (11, 12) (W1 in FIG. 12), the distance between the coupled line 11 and the coupled line 12 may be increased. For this purpose, the thickness (B) of the shield case 1 is increased. Need to be larger.
In general, in a λ / 4 coupling type 3 dB hybrid circuit using a coaxial feeder tube as a terminal, the conduction mode is a TEM mode. However, when the thickness (B) of the shield case 1 is 100 mm, TE ₁₁ (H ₁₁ ) A mode is generated, and the TE ₁₁ (H ₁₁ ) mode electromagnetic wave is coupled between the terminal (T 1) and the terminal (T 2), and the electrical characteristics deteriorate.
[0005]
On the other hand, in recent years, in addition to conventional analog television broadcasting, digital television broadcasting is about to be started due to technological progress.
The modulation wave of the orthogonal frequency division multiplex (OFDM) modulation method employed in the digital television broadcast is higher in peak voltage value than the NTSC modulation wave of the conventional analog television broadcast. Has the feature of being large.
Therefore, when the hybrid circuit shown in FIGS. 11 and 12 is used to branch or synthesize a modulated wave of the orthogonal frequency division multiplexing modulation system, it is necessary to increase the power capacity. It is necessary to increase the size of the shield case 1 and the outer diameter of the inner conductor of the terminal as compared with the wavelength (λo) of the design center frequency.
[0006]
However, in the conventional hybrid circuits shown in FIGS. 11 and 12, in order to increase the power capacity, the size of the shield case 1 is made larger than the wavelength (λo) of the design center frequency of the hybrid circuit, or If the outer diameter of the inner conductor of the terminal is increased, the electrical characteristics deteriorate for the reason described above, and therefore there is a problem that it cannot be used for the above-described application.
The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a λ / 4 coupling type capable of improving the power capacity without deteriorating the electrical characteristics. The object is to provide a 3 dB hybrid circuit.
The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.
[0007]
[Means for Solving the Problems]
Of the inventions disclosed in this application, the outline of typical ones will be briefly described as follows.
That is, the present invention provides a shield case having first to fourth side walls, a first terminal fixed to the first side wall, a second terminal fixed to the second side wall, A third terminal fixed to the third side wall facing the second side wall, a fourth terminal fixed to the fourth side wall facing the first side wall, and the shield terminal disposed in the shield case. And a first coupling line having one end electrically connected to the first terminal and the other end electrically connected to the third terminal, and being disposed in the shield case, and having one end being the second terminal A hybrid circuit comprising a terminal and a second coupling line whose other end is electrically connected to the fourth terminal, wherein the first coupling line includes the first terminal and the fourth terminal. Or a straight line connecting the second terminal and the third terminal And inclined slope portion that will be placed inclined, the said continuous to the inclined portion is arranged along the first side wall, the first terminal connection part connected to the first terminal, the inclined And a second terminal connection portion connected to the third terminal, the second coupling line being connected to the first side wall, the second connection line being connected to the third terminal. An inclined portion of the first coupling line is disposed to be inclined with respect to a straight line connecting the terminal and the fourth terminal or a straight line connecting the second terminal and the third terminal. An inclined portion disposed adjacent to the inclined portion; a first terminal connecting portion that is continuous with the inclined portion and is disposed along the second side wall; and is connected to the second terminal; and the inclined portion A second portion connected to the fourth terminal and arranged along the fourth side wall. And a child connection section, the line length of the first and second coupling line L, La and the length of the inclined portion, when the λo the wavelength of the design center frequency of the hybrid circuit, 0.8Ramudao / 2 ≦ L ≦ 1.2λo / 2 and 0.9λo / 4 ≦ La ≦ 1.1λo / 4 are satisfied.
In a preferred embodiment of the present invention, when the width of the first and second coupled lines is W, W ≧ λo / 16 is satisfied.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof will be omitted.
FIG. 1 is a plan view showing an upper plane of a λ / 4 coupled 3 dB hybrid circuit (hereinafter simply referred to as a hybrid circuit) according to an embodiment of the present invention.
FIG. 2 is a side view showing a side surface of the hybrid circuit shown in FIG. 1 viewed from the direction of the terminal T1.
FIG. 3 is a cross-sectional view showing a cross section taken along the line AA ′ shown in FIG.
As shown in FIGS. 1, 2, and 3, also in the present embodiment, two coupled lines (11, 12) are arranged in a shield case (housing) 1, and the coupled line 11 has one end. There internal conductor 13 of the _first terminal _{T 1,} the other end is connected to the third terminal _{T 3} of the inner conductor 13 _3, the coupling line 12, to the inner conductor 13 _{and second} end a second terminal _{T 2} and the other end connected to the inner conductor 13 ₄ of the fourth terminal _{T 4.}
However, in the present embodiment, the coupling lines (11, 12) are not formed in a single plate shape (or in a straight line shape) as in the conventional hybrid circuit, but in a single conductive plate. It is formed by bending both sides of the inside.
In the present embodiment also, the four terminals (T _{1 to} T ₄ ) are coaxial feeders each composed of an inner conductor (13 _{1 to} 13 ₄ ) and an outer conductor (14 _{1 to} 14 ₄ ). Consists of.
[0009]
FIG. 4 is a diagram for explaining the coupled line 11 of the present embodiment, and is a view of the coupled line 11 of the present embodiment as viewed from above.
As shown in FIG. 4, the coupled line 11 of the present embodiment is arranged so as to be inclined with respect to a straight line connecting the terminal T ₁ and the terminal T ₄ or a straight line connecting the terminal T ₂ and the terminal T _3. And the terminal connecting portions (3, 4) formed by bending the inclined portion 2 on both sides of the inclined portion 2 with respect to the inclined portion.
Here, the terminal connection portion 3 is connected to the inner conductor 13 _first terminal _{T 1,} the terminal connecting portion 4 is connected to the inner conductor 13 _third terminal _{T 3.} The coupled line 12 has the same shape as the coupled line 11.
As shown in FIG. 3, an inclined portion 2 of the coupling line 11, and the inclined portion 2 of the coupling line 12 are arranged close to each other, (in FIG. 4 La) this length of the inclined portion, the hybrid circuit When the wavelength of the design center frequency is λo, it is approximately λo / 4 (La≈λo / 4), and the length of the terminal connection portions (3, 4) (Lb in FIG. 4) is approximately λo / 8. (Lb≈λo / 8).
Therefore, since the line length (La + 2Lb) of the coupled lines (11, 12) is approximately λo / 2, in the present embodiment, between the terminal T ₁ and the terminal T ₃ and also between the terminal T ₂ and the terminal T _4. It is possible to prevent unwanted waves from being coupled to each other.
[0010]
FIG. 5 is a view for explaining the width of the coupled line of the present embodiment, and is a view seen from the direction B of FIG.
In the present embodiment, the width of the coupled lines (11, 12) (W in FIG. 5) can be W ≧ λo / 16.
For example, if W is 70 mm and the thickness of the coupled lines (11, 12) is 2 mm, the perimeter when the section is cut by a plane orthogonal to the extending direction of the coupled lines (11, 12) is 144 mm (= 70 × 2 + 2 × 2).
Further, when the outer diameter of the inner conductor 13 of the coaxial feeding pipe constituting the terminal is 33.4 mm in relation to the power capacity, as described above, the circumferential length of the inner conductor 13 of the coaxial feeding pipe is 105 ( ≈π × 33.4).
Therefore, in the present embodiment, the peripheral length of the coupled lines (11, 12) is about 1.37 (≈144 / 105) times the circumferential length of the inner conductor 13 of the coaxial feeder tube.
This means that the hybrid circuit of this embodiment has a current capacity of about 1.37 times and a power capacity of about 1.88 (≈1.37 × 1.37) as compared with the conventional hybrid circuit. You can see that
Thus, according to the present embodiment, it is possible to improve the power capacity as compared with the conventional hybrid circuit.
In the hybrid circuit of the present embodiment, the line length (L) of the coupled lines (11, 12) is 0.8λo / 2 ≦ L ≦ 1.2λo / 2, and the coupled lines (11, 12). If the length (La) of the inclined portion satisfies 0.9λo / 4 ≦ La ≦ 1.1λo / 4, the above-described functions and effects can be obtained.
[0011]
In the hybrid circuit of the present embodiment, the terminal _{T 1} - voltage coupling coefficient _{S 12} of the terminal _{T 2,} the terminal _{T 2} - terminal _{T 1} of the voltage coupling coefficient _{S 21,} the terminal _{T 3} - voltage coupling coefficient of the terminal _{T 4 S 34} The voltage coupling coefficient S ₄₃ between the terminal T ₄ and the terminal T ₃ is expressed by the following equation (1).
[Expression 1]

Here, assuming that C = 1 / √2 and θ = 90 °, the expression (1) is expressed as the following expression (2).
[Expression 2]
_{S 12 = S 21 = S 34} = S 43 = 1 / √2 ········· (2)
The terminal _{T 1} - voltage coupling coefficient _{S 13} of the terminal _{T 3,} the terminal _{T 3} - voltage coupling coefficient _{S 31} of the terminal _{T 1,} the terminal _{T 2} - voltage coupling coefficient _{S 24} of the terminal _{T 4,} the terminal _{T 4} - terminal T voltage coupling coefficient _{S 42} of ₂ is expressed by the following equation (3).
[Equation 3]

Here, assuming that C = 1 / √2 and θ = 90 °, the expression (1) is expressed as the following expression (4).
[Expression 4]
S ₁₃ = S ₃₁ = S ₂₄ = S ₄₂ = −j / √2 (4)
[0012]
6 to 8 are graphs showing the electrical characteristics of an example of the hybrid circuit of the present embodiment.
The graphs shown in FIGS. 6 to 8 are graphs showing the results of actually making a prototype of the hybrid circuit of the present embodiment and measuring its electrical characteristics.
The dimensions of the prototype hybrid circuit are as follows.
(1) A cube in which the length of one side (Lc shown in FIG. 3) inside the shield case 1 is 100 mm and the height (Ld shown in FIG. 2) is 100 mm.
(2) Shape of the coupled line (11, 12) The length of the inclined portion 2 is 150 mm (therefore, λo is 600 mm, fo is 0.5 GHz), the width (W in FIG. 4) is 70 mm, and the thickness is 2 mm.
(3) The inner diameter of the inner conductor 13 is 31.3 mm, and the outer diameter is 33.4 mm.
(4) The outer conductor 14 has an inner diameter of 76.9 mm and an outer diameter of 79.4 mm.
[0013]
Figure 6 is actually prototype terminal T of the hybrid circuit of the present embodiment ₁ - is a graph showing the phase characteristic of the output voltage between the terminals T ₃ - and the phase of the output voltage between the terminals T _2, the terminal T ₁ .
In FIG. 6, the horizontal axis is frequency (MHz), the memory interval is 50 MHz, the center frequency is 0.6 GHz, the vertical axis is the phase amount, and the memory interval is 45 °.
Further, A represents the phase of the output voltage between the terminal T ₁ and the terminal T ₂ , B represents the phase of the output voltage between the terminal T ₁ and the terminal T ₃ , and as can be seen from FIG. 6, a voltage is applied to the terminal T _1. upon application, the output voltage output from the terminal T _2, the phase difference between the output voltage output from the terminal T ₃ has become 90 °.
In the graph of the phase of the output voltage between the terminal T ₁ and the terminal T ₂ in FIG. 6, the phase when the frequency is 0.47 GHz (the point 2 in the graph of A in FIG. 6) is −130.4 °, The phase when the frequency is 0.503 GHz (point 1 in the graph of A in FIG. 6) is −144.92 °, and the phase when the frequency is 0.692 GHz (point 3 in the graph of A in FIG. 6) is The phase at 131.25 ° and a frequency of 0.770 GHz (point 4 in the graph of FIG. 6A) is 95.775 °.
Further, in the graph of the phase of the output voltage between the terminal T ₁ and the terminal T ₃ in FIG. 6, the phase when the frequency is 0.47 GHz (the point 2 in the graph of B in FIG. 6) is 139.51 °, the frequency When the frequency is 0.503 GHz (point 1 in the graph of B in FIG. 6), the phase is 124.84 °, and when the frequency is 0.692 GHz (point 3 in the graph of B in FIG. 6), the phase is 40.84 °. The phase at 843 ° and a frequency of 0.770 GHz (point 4 in the graph of B in FIG. 6) is 4.0746 °.
[0014]
Figure 7 is actually terminals of the hybrid circuit of the present embodiment a prototype T ₁ - is a graph showing the attenuation characteristic of the output voltage between the terminals T ₃ - the output voltage between the terminals T _2, the terminal T _1.
In FIG. 7, the horizontal axis is frequency (MHz), the memory interval is 50 MHz, the center frequency is 0.6 GHz, the vertical axis is the amount of attenuation, and the memory interval is 1 dB.
Further, A represents the attenuation amount of the output voltage between the terminal T ₁ and the terminal T ₂ , and B represents the attenuation amount of the output voltage between the terminal T ₁ and the terminal T ₃ , and as can be seen from FIG. 7, 0.47 GHz to 0 When a voltage is applied to the terminal T ₁ between .70 GHz, the attenuation amount of the output voltage output from the terminal T ₂ and the attenuation amount of the output voltage output from the terminal T ₃ are approximately 3 dB. ing.
In the graph of the attenuation amount of the output voltage between the terminal T ₁ and the terminal T _{2 in} FIG. 7, the attenuation amount is −3.5088 dB when the frequency is 0.47 GHz (point 2 in the graph of A in FIG. 7). When the frequency is 0.503 GHz (point 1 in the graph of FIG. 7A), the attenuation is −3.2935 dB, and the frequency is 0.692 GHz (point 3 of the graph in FIG. 7A). The amount is −3.0524 dB, and the attenuation is −3.5005 dB when the frequency is 0.770 GHz (point 4 in the graph of A in FIG. 7).
Further, in the graph of the attenuation amount of the output voltage between the terminal T ₁ and the terminal T _{3 in} FIG. 7, the attenuation amount is −2.5969 dB when the frequency is 0.47 GHz (point 2 in the B graph of FIG. 7). When the frequency is 0.503 GHz (point 1 in the graph of B in FIG. 7), the attenuation is −2.7744 dB, and the frequency is 0.692 GHz (point 3 in the graph of B in FIG. 7). The amount is −3.089 dB and the attenuation is −2.9125 dB when the frequency is 0.770 GHz (point 4 in the graph of B in FIG. 7).
[0015]
FIG. 8 is a graph showing the attenuation characteristics of the output voltage between the terminal T ₁ and the terminal T ₄ and the output voltage between the terminal T ₂ and the terminal T ₃ of the hybrid circuit according to the present embodiment actually manufactured.
In FIG. 8, the horizontal axis is frequency (MHz), the memory interval is 50 MHz, the center frequency is 0.6 GHz, the vertical axis is the amount of attenuation, and the memory interval is 10 dB.
Further, A represents the attenuation amount of the output voltage between the terminal T ₁ and the terminal T ₄ , and B represents the attenuation amount of the output voltage between the terminal T ₂ -the terminal T _{3 and the} terminal T ₁ -the terminal T ₃ , as can be seen from FIG. to, among 0.47GHz～0.70GHz, when a voltage is applied to the terminal _{T 1,} the attenuation amount of the output voltage output from the terminal _{T 2,} and, when a voltage is applied to the terminal _{T 2,} attenuation amount of the output voltage output from the terminal T ₃ is almost 30 dB, when a voltage is applied to the terminal T _1, the output voltage output from the terminal T _2, and the voltage at the terminal T ₂ upon application, the output voltage output from the terminal T ₃ can be seen to have been sufficiently attenuated.
In the graph of the attenuation amount of the output voltage between the terminal T ₁ and the terminal T _{4 in} FIG. 8, the attenuation amount is −25.304 dB when the frequency is 0.47 GHz (point 2 in the graph of A in FIG. 8). When the frequency is 0.503 GHz (point 1 in the graph of FIG. 8A), the attenuation is −2.7744 dB, and when the frequency is 0.692 GHz (point 3 of the graph in FIG. 8A). The amount is -20.439 dB, and the attenuation is -16.235 dB when the frequency is 0.770 GHz (point 4 in the graph of A in FIG. 8).
Further, in the graph of the attenuation amount of the output voltage between the terminal T ₂ and the terminal T _{3 in} FIG. 8, the attenuation amount is −25.276 dB when the frequency is 0.47 GHz (point 2 in the B graph in FIG. 8). When the frequency is 0.503 GHz (point 1 in the graph of B in FIG. 8), the attenuation is −27.986 dB, and the frequency is 0.692 GHz (point 3 in the graph of B in FIG. 8). The amount is −16.878 dB when the frequency is −21.04 dB and the frequency is 0.770 GHz (point 4 in the graph of B in FIG. 8).
[0016]
FIG. 9 is a block diagram showing a schematic configuration of an antenna duplexer using the hybrid circuit of the present embodiment.
In the antenna sharing device shown in FIG. 9, the fourth terminal (T ₂₄ ) of the second hybrid circuit 22 and the first terminal (T ₄₁ ) of the fourth hybrid circuit 24 are connected to each other, and The first terminal (T ₂₁ ) of the second hybrid circuit 22 is connected to the non-reflecting terminator (R), and the fourth terminal (T ₄₄ ) of the fourth hybrid circuit 24 is connected to the antenna (ANT). Is done.
The first terminal (T ₁₁ ) of the first hybrid circuit 21 is connected to a transmitter that outputs a transmission wave of the first channel (ch1), and the first terminal of the third hybrid circuit 23 The terminal (T ₃₁ ) is connected to a transmitter that outputs a transmission wave of the second channel (ch2).
Further, the fourth terminal (T ₁₄ ) of the first hybrid circuit 21 and the fourth terminal (T ₃₄ ) of the third hybrid circuit 23 are connected to the non-reflection terminator (R).
[0017]
Further, between the second terminal (T ₁₂ ) of the first hybrid circuit 21 and the second terminal (T ₂₂ ) of the second hybrid circuit 22, as well as the third terminal of the first hybrid circuit 21. A first bandpass filter (30, 31) is connected between the terminal (T ₁₃ ) and the third terminal (T ₂₃ ) of the second hybrid circuit 22.
Similarly, between the second terminal (T ₃₂ ) of the third hybrid circuit 23 and the second terminal (T ₄₂ ) of the fourth hybrid circuit 24 and the third terminal of the third hybrid circuit 23. The second band pass filter (32, 33) is connected between the terminal (T ₃₃ ) and the third terminal (T ₄₃ ) of the fourth hybrid circuit 24. Here, the first hybrid circuit 21, the second hybrid circuit 22, and the band-pass filter (30, 31) include a constant impedance band-pass filter that passes the transmission wave of the first channel (ch1), and The third hybrid circuit 23, the fourth hybrid circuit 24, and the band pass filters (32, 33) constitute a constant impedance band pass filter that passes the transmission wave of the second channel (ch2).
Here, the hybrid circuit of the present embodiment is used as the hybrid circuit (21 to 24).
[0018]
The operation of the antenna sharing device shown in FIG. 9 will be briefly described below.
The transmission waves of the first channel (ch1) input from the first terminal (T ₁₁ ) of the first hybrid circuit 21 pass through the bandpass filters (30, 31), respectively, and pass through the second hybrid circuit 22. And output from the fourth terminal (T ₂₄ ) of the second hybrid circuit 22.
The transmission wave of the first channel (ch1) output from the second hybrid circuit 22 is input to the fourth hybrid circuit 24, and is totally reflected by the band-pass filters (32, 33). It is output from the fourth terminal (T ₄₄ ) of the circuit 24 and radiated from the antenna (ANT).
In addition, the transmission wave of the second channel (ch2) input from the first terminal (T ₃₁ ) of the third hybrid circuit 23 passes through the bandpass filters (32, 33), respectively, and passes through the fourth hybrid. The signal is input to the circuit 24, output from the fourth terminal (T ₄₄ ) of the fourth hybrid circuit 24, and radiated from the antenna (ANT). Although the invention made by the present inventor has been specifically described based on the above-described embodiment, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. Of course.
[0019]
【The invention's effect】
The effects obtained by the representative ones of the inventions disclosed in the present application will be briefly described as follows.
According to the present invention, in the λ / 4 coupled 3 dB hybrid circuit, it is possible to improve the power capacity without impairing the electrical characteristics.
[Brief description of the drawings]
FIG. 1 is a plan view showing an upper plane of a λ / 4 coupled 3 dB hybrid circuit according to an embodiment of the present invention.
FIG. 2 is a side view showing one side of the λ / 4 coupled 3 dB hybrid circuit shown in FIG. 1;
3 is a cross-sectional view showing a cross section taken along the line AA ′ shown in FIG. 2;
FIG. 4 is a diagram for explaining a coupled line according to an embodiment of the present invention.
FIG. 5 is a diagram for explaining the width of a coupled line according to an embodiment of the present invention.
[6] of the present invention the form of lambda / 4 coupling type 3dB hybrid circuit of the terminal T ₁ - phase characteristic between the output voltage between the terminals T ₃ - the output voltage between the terminals T _2, the terminal T ₁ It is a graph which shows.
[Figure 7] embodiment of the present invention lambda / 4 coupling type 3dB hybrid circuit of the terminal T ₁ - shows the attenuation characteristic of the output voltage between the terminals T ₃ - the output voltage between the terminals T _2, the terminal T ₁ It is a graph.
FIG. 8 shows attenuation characteristics of an output voltage between a terminal T ₁ and a terminal T ₄ and an output voltage between a terminal T ₂ and a terminal T ₃ of the λ / 4 coupled 3 dB hybrid circuit according to the embodiment of the present invention. It is a graph.
FIG. 9 is a block diagram showing a schematic configuration of an antenna duplexer using the λ / 4 coupled 3 dB hybrid circuit according to the embodiment of the present invention.
FIG. 10 is a schematic perspective view showing the structure of a conventional hybrid circuit.
FIG. 11 is a cross-sectional view of a main part showing the structure of a conventional hybrid circuit.
FIG. 12 is a side view showing a side surface of a conventional hybrid circuit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Shield case, 2 ... Inclined part, 3, 4 ... Terminal connection part, 11, 12 ... Coupling line, 13 ... Internal conductor, 14 ... External conductor, 15 ... Spacer, 21-24 ... Hybrid circuit, 30-33 ... Band pass filter, ANT ... antenna, R ... non-reflection terminator.

Claims (2)

A shield case having first to fourth side walls ;
A first terminal fixed to the first side wall;
A second terminal fixed to the second side wall;
A third terminal fixed to a third side wall facing the second side wall;
A fourth terminal fixed to a fourth side wall facing the first side wall;
A first coupling line disposed in the shield case, having one end electrically connected to the first terminal and the other end electrically connected to the third terminal;
A hybrid circuit that is arranged in the shield case and includes a second coupling line having one end connected to the second terminal and the other end electrically connected to the fourth terminal,
The first coupling line is disposed to be inclined with respect to a straight line connecting the first terminal and the fourth terminal or a straight line connecting the second terminal and the third terminal. and the inclined slope portion that,
A first terminal connecting portion that is continuous with the inclined portion and is disposed along the first side wall and connected to the first terminal ;
A second terminal connecting portion that is continuous with the inclined portion and disposed along the third side wall and connected to the third terminal;
The second coupling line is disposed to be inclined with respect to a straight line connecting the first terminal and the fourth terminal or a straight line connecting the second terminal and the third terminal. And an inclined portion disposed in proximity to the inclined portion of the first coupling line,
A first terminal connecting portion that is continuous with the inclined portion and is disposed along the second side wall and connected to the second terminal ;
A second terminal connection portion connected to the fourth terminal, the second terminal connection portion being continuous with the inclined portion and disposed along the fourth side wall ;
When the line length of the first and second coupled lines is L, the length of the inclined portion is La, and the wavelength of the design center frequency of the hybrid circuit is λo, 0.8λo / 2 ≦ L ≦ 1.2λo / 2. A hybrid circuit that satisfies 0.9λo / 4 ≦ La ≦ 1.1λo / 4. 2. The hybrid circuit according to claim 1, wherein W ≧ λo / 16 is satisfied, where W is a width of the first and second coupled lines.

Images